Tomorrow night, the 24th, the planets will appear to be only 2 1/2 degrees apart, or about 5 times the width of the full moon. Venus is the brightest of the three. If you watch the planets over a few days, it will be easy to see them move relative to one another as their orbits carry them around the sun. Saturn will appear to sink closer to the sun, while Venus and Mercury are climbing higher in the sky.
Take a few minutes over the next few days and take in the spectacle. More detailed explanations and graphs can be found from the Sky & Telescope website.